Vibrating device with a heat insulated treatment chamber, particularly a vibrating mill

ABSTRACT

In a vibrating device provided with a treatment chamber surrounded by a heat insulating jacket, the heat insulating material of this jacket is surrounded by a solid outer jacket, for instance made of plastic, and this outer jacket is rigidly connected by solid connecting members with the outer circumference of a tube the interior of which forms said treatment chamber. The connecting members may comprise radial tongues bent inwardly from said outer jacket or straps wrapped around said tube and attached with their ends to said solid outer jacket or thin discs arranged in the space between the inner wall of said solid outer jacket and the outer wall of said tube. The discs are provided with a plurality of circular series of apertures to reduce the heat conductivity of the discs.

United States Patent 1 Langmaack et al.

[ 1 May 28, 1974 VIBRATING DEVICE WITH A HEAT INSULATED TREATMENTCHAMBER, PARTICULARLY A VIBRATING MILL Inventors: Jiirgen Langmaack,Niederkassel;

Helmut Haas, Cologne, both of Germany Klockner-Humboldt-DeutzAktiengesellschaft, Cologne, Germany Filed: Dec. 15, 1971 Appl. No.:208,291

Assignee:

Foreign Application Priority Data Dec. 24, 1970 Germany ..,2063688 US.Cl. 259/72, 220/9 R Int. Cl B0lf 11/00 Field of Search 220/9 R, 9 A, 15;259/72,

259/1 R, DIG. 42, DIG. 43, DIG. 44, DIG. 41

References Cited UNITED STATES PATENTS 7/1917 Frank 220/15Pheteplace...., 220/9 A UX 1,973,880 9/1934 Moody 220/) D 2,416,0172/1947 Nol'zinger 2,763,321 9/1956 Schuster 220/15 X PrimaryExaminer-Robert W. Jenkins Attorney, Agent, or FirmHill, Gross, Simpson,Van Santen, Steadman, Chiara & Simpson [57] ABSTRACT In a vibratingdevice provided with a treatment chamber surrounded by a heat insulatingjacket, the heat insulating material of this jacket is surrounded by asolid outer jacket, for instance made of plastic, and this outer jacketis rigidly connected by solid connecting members with the outercircumference of a tube the interior of which forms said treatmentchamber.

The connecting members may comprise radial tongues bent inwardly fromsaid outer jacket or straps wrapped around said tube and attached withtheir ends to said solid outer jacket or thin discs arranged in thespace between the inner 'wall of said solid outer jacket and the outerwall of said tube. The discs are provided with a plurality of circularseries of apertures to reduce the heat conductivity of the discs.

10 Claims, 6 Drawing Figures PATENTED MAY 2 8 1334 saw 1 BF VIBRATINGDEVICE WITH A I-IEAT INSULATED TREATMENT CHAMBER, PARTICULARLY AVIBRATING MILL The invention relates to a vibrating device which isequipped with a treatment chamber surrounded by an insulating jacket andparticularly relates to a vibrating mill.

In such devices, particularly vibrating mills or oscillating conveyors,in which the material is subjected simultaneously to a temperaturetreatment, particularly a cooling treatment or low-temperaturetreatment, respectively, the problem is to construct the insulatingjacket in such manner that the same is capable of withstanding the highacceleration forces which, for instance, may amount to a value which istimes the value of the acceleration due to gravity. On the other hand,the attachment of the insulating jacket to the treatment chamber of thevibrating device has to be effected in such manner that the securingmeans transmit only very small amounts of heat from the exterior towardthe interior or from the interior toward the exterior. This is the moreimportant, the higher the difference in temperature is between theinterior of the treatment chamber and the surrounding atmosphere,because these securing means may cause substantial losses in temperaturewhich endanger the economy of the method practiced with the device.

It is an object of the invention to provide the vibrating device with aninsulating jacket which is able to withstand the mechanical stresses andcomplies with the necessary insulating requirements to which suchvibrating devices are subjected.

In accordance with the invention, a solid outer jacket on the insulatingjacket is rigidly connected with the walls of the treatment chamber byconnecting elements having the smallest possible cross-sectional area.When this is done, the insulating material arranged between the walls ofthe treatment chamber and the solid outer jacket is subjected in respectof its strength solely to inertia forces which by means of their ownmass may act upon the insulating material. From the inner side and fromthe outer side, the insulating material is held against the wall of thetreatment chamber by means of the outer jacket which is rigidlyconnected to the treatment chamber, so that relative movements of theinsulating material under the influence of the vibrating movement cannotdevelop. Since furthermore the cross-sectional area of the connectingelements between the outer jacket and the treatment chamber have thesmallest possible cross-section, it is assured that in spite of thedirect connection between the treatment chamber and the outer jacket,the conduction of heat from the exterior toward the interior or from theinterior toward the exterior, respectively, is reduced to a minimum.

Another object of the invention is that the connecting elements betweenthe outer jacket and the treatment chamber in each of the respectiveattachment ranges are constructed as strap means which preferably arearranged in the end range of the outer jacket or a section of the outerjacket. In such an arrangement a verysimple attachment of the outerjacket to the treatment chamber is possible since in the range of theends of the outer jacket or the sections of the outer jacket the strapmeans are easily accessible, so that the same in a simple manner producea rigid connection between the outer jacket and the treatment chamber bysuitable meansfor instance, by means of welding, gluing or screws.

In an advantageous embodiment of the invention, the connecting elementsbetween the treatment chamber and the outer jacket comprise a materialof low-heat conductivity. In this manner, the insulating effect of theconnecting elements when having a very small crosssectional area can beincreased, or if in view of the stresses during the operation largercross-sections have to be selected, the enlargement of suchcross-section compensates for a suitable heat transmission by heatconductivity. Depending upon the type of the connecting elements, it maybe sufficient when the same are made only partially of a material havinga low heat conductivity.

In another embodiment of the invention, the solid outer jacket is madeof a plastic, preferably of a plastic reinforced by fibers. This has theadvantage that on the one hand, a solid outer skin is provided for theprotection of the insulating material, which skin is also resistant tomechanical stresses from the exterior which, however, on the other hand,in view of the customary small specific weight of the plastic, whichcomes into consideration for the material of the outer jacket reducesthe mass of the same. In this manner, the advantage is obtained that thestresses acting on the connecting elements under the influence of themass forces created by the vibrating movement are noticeably reduced bya suitable decrease of the mass of the outer jacket.

For improving the insulating effect, the invention provides also thatthe outer jacket on its outer surface is provided with a coating whichreflects heat rays. When in this manner the difference in temperaturebetween the interior of the treatment chamber and the environment isvery high, particularly when practicing a low-temperature process in thetreatment chamber, the insulating effect of the insulating material isimproved.

The invention will now be described in greater detail with reference tothe accompanying drawings which disclose a few embodiments of theinvention and additional features of the same.

In the drawings:

FIG. 1 illustrates diagrammatically a tubular vibrating mill withinsulated grinding tubes.

FIG. 2 illustrates in an enlarged longitudinal sectional view, a portionof a grinding tube of a vibrating mill.

FIG. 3 is an enlarged cross-sectional view along the line III-III ofFIG. 1.

FIG. 4 illustrates a development of the outer jacket in the range of thecross-sectional view IIIIII of FIG. 1.

FIG. 5 illustrates another embodiment of the connecting elements whichmay be used; and

FIG. 6 illustrates still another embodiment of the connecting elementswhich may be used.

Referring to FIG. 1, the illustrated tubular vibrating mill is providedwith two heat insulated grinding tubes 1 and 2 arranged in spacedrelation one above the other and extending with their axes in ahorizontal direction. This tubular vibrating mill with itsheat-insulated grinding tubes is suitable for performing grindingoperations at low and very low temperatures, respectively. For thispurpose, the two horizontally disposed grinding tubes 1 and 2 are eachprovided with an insulating jacket 10 and are arranged in a supportingframe 3 mounted for vibratory movement. The supporting frame 3 isprovided with a not-illustrated vibration-producing device. The grindingtubes 1 and 2 are connected with the mentioned supporting frame 3 bymeans of clamping straps 4. The upper left-hand end of the grinding tube1 is connected with a vertically disposed insulated feed pipe 5. Thematerial which has been ground leaves the left-hand end of the lowergrinding tube 2 through downwardly divided discharge pipe 6 which alsois insulated. The two right-hand ends of the vertically spaced paralleland horizontal grinding tubes 1 and 2 are connected with each other by avertically disposed insulated pipe 7. The insulating jacket of eachgrinding tube owing to the attachment of the grinding tubes to thesupporting frame and owing to the particular arrangement of the feedpipe and the discharge pipe is subdivided into individual sections. Onesection extends from each end to a separating joint on the feed head ordischarge head, respectively; a further section extends from the jointto the fastening means of the grinding tube to the supporting frame.Furthermore, one section is arranged between the two fastening points.Such a subdivision of the insulating jacket isnot required, however, inother devices in which the construction permits the arrangement of anundivided insulating jacket.

FIG. 2 illustrates in a longitudinal section the upper portion of thefeed end of the tubular vibrating mill on an enlarged scale. Thegrinding tube 1 is provided at its left-hand end with an outwardlyextending flange 8 to which is attached by means of bolts and nuts theoutwardly extending flange of a feed head 9 which closes the left-handend of the tube 1. This feed head 9 has attached thereto theupwardly-extending feed pipe 5. The outer surface of the grinding tube 1is completely surrounded by an insulating jacket 10 comprising a thicklayer of insulating material on the outside of which is placed a solidouter shell or jacket 11. The insulating jacket 10 in accordance withthe construction of the tubular vibrating mill is subdivided into anumber of sections. In order to obtain a rigid connection between thegrinding tube 1 and the outer solid jacket 11, the outer jacket of whichin accordance with the invention gives the insulating material asufficient hold even at very high accelerating values, it is necessaryto provide at least in the end ranges of each section of insulatingjacket, a number of connecting elements between the outer jacket and thegrinding tube.

In the range of the flange, the connecting elements could consist inaccordance with one embodiment of the invention, of a tongue-shapedradial extension 12 of the solid outer jacket 11, as this is illustratedin FIG. 4, which shows a development of the outer jacket 11. As shown inthe sectional view of FIG. 2, these tongueshaped extensions are bent asshown in FIG. 4 along the dotted lines, namely inwardly and then againwith their extreme outer ends in axial direction of the grinding tubesin such a manner that the outermost ends of these tongues can be fixedlysecured to the outer circumference ofthe flange 8, preferably by awelding operation.

FIG. 3 illustrates an end view of the grinding tube 1 with the feed head9 removed therefrom in order to show clearly the position andarrangement of the radial tongues 12. The advantage of this embodimentis that the entire construction of the connecting elements is verysimple. The outwardly extending and abutting flanges 8 and 9 of thegrinding tube 1 and of the feed head 9, respectively, are connected witheach other by bolts and nuts, as shown in FIG. 2.

In place of tongues 12 having a rectangular crosssection, as shown inthe FIGS. 2, 3 and 4, another embodiment of the invention has certainadvantages when the outer jacket 11 is connected by means of tubularmembers with the grinding tube 1. This is particularly then of advantagewhen owing to great accelerations of the grinding tube caused by thevibrating movement, the outer jacket also is subjected to substantialinertia forces, so that the tubular form of the connecting membersinsures a greater strength of the connecting elements, while on theother hand the cross-sectional tubular members insure a very small heatconduction.

In the vibrating mill selected as an example of the invention, eachgrinding tube is force-lockingly connected with the supporting frame 3by clamping straps 4. When using insulated grinding tubes, then in eachfastening range a supporting ring 13 is placed around the grinding tube,and this supporting ring 13 is connected rigidly by radial members 14consisting of solid insulating material with the grinding tube 1. Thesolid insulating material may, for instance, comprisepolytetrafluorethylene. This supporting ring 13 may at the same timeadvantageously be used as a fastening element for the adjacent ends ofthe sections of the solid outer jacket 11. For this purpose, theadjacent ends of the outer jacket 11 are caused each to engage slidablyan annular groove 15 in the supporting ring 13 and are then weldedthereto.

FIG. 5 illustrates, by way of example, another connecting element whichmay be arranged between the solid outer jacket 11 and the grinding tube1 or 2 of a vibrating mill. FIG. 5 illustrates in an end view similar tothe section III-III in FIG. 1, a connecting element which comprises arelatively thin circular disc 16 which is provided over its entiresurface with apertures. In this embodiment, the apertures comprise slots17 extending concentrically with respect to the center of this disc 16.According tothe invention, the apertures or slots are arranged in anumber of rows concentrically placed about the axis of the center ofthis disc, whereby the apertures or slots in adjacent circular rows areoffset with respect to one another. The advantage of this particulararrangement of the aperture and slots is that there remains between theapertures or slots solid portions which first of all may transmit heatfrom the outer jacket to the inner chamber or vice versa, and this heatconduction is substantially increased with respect to the radialdistance between the outer jacket and the treatment chamber. In thismanner, it is possible to reduce the temperature loss within the rangeof the securing elements substantially even though the disc may consistof material which is a good heat conductor.

FIG. 6 illustrates another embodiment of a connecting element for thevibrating mill of the present invention. In this embodiment, thetreatment chamber-for instance the grinding tube l-is provided atopposite sides with at least two flexible straps 18 and 19 or wireswhich are wrapped around the grinding tube 1 and which at their ends areattached to the solid outer jacket 11. This type of connecting elementis particularly suitable for all fastening ranges which do not lie anymore at the end range of the outer jacket and, therefore, need not beslidably moved over extensions of the treatmentchamber, such asoutwardly projecting flanges, or which for other reasons are no longeraccessible from the outside. In this arrangement, the straps or wiresare first fixedly attached with one of their ends to the outer jacket,while the other end has a suitable length and is loosely pushed throughan opening in the outer jacket. Only then when the correct position ofthe outer jacket with respect to the treatment chamber has beenobtained, the loose end of the straps or wires is tensioned and isfixedly attached to the outer jacket.

In the event that the thickness of the outer jacket or the strength ofthe material is not sufficient, it is necessary to provide in thefastening range of the straps on the outer jacket a suitable clampingring. The arrangement of such a clamping ring permits the attachment ofclamping elements which make a re-tensioning of the straps possible.

The invention is not limited to the examples of the connecting elementswhich have been described in connection with a tubular cross-section ofthe treatment chamber and is also not limited to vibrating mills. Infact, the mentioned connecting elements are suitable for any vibratingdevice which is provided with a treatment chamber surrounded by aninsulating jacket. According to the basic principle of the invention, itis solely of importance that a solid connection is made between theouter jacket and the wall of the treatment chamber and that theconnecting elements between the same have cross-sectional areas whichare so small that a heat conduction is kept as small as possible.

What we claim is:

1. In a vibrating device having a treatment chamber with the wallsurrounded by an insulator sleeve having an outer jacket, said chamberbeing supported in a frame which is provided with a vibration producingdevice, the improvements comprising a fixed clamping strap connected tothe frame, and connecting elements disposed between the wall of thetreatment chamber and the clamping strap to rigidly interconnect thechamber to the clamping strap, said connecting elements having across-sectional area which is small as possible to prevent transfer ofheat between the strap and the wall of the chamber.

2. In a vibrating device according to claim 1, wherein the connectingelements are constructed of a plurality of members disposed between theclamping strap and the wall of the treatment chamber.

3. In a vibrating device according to claim 2, wherein the member of theconnecting elements include a tubular member spaced from the wall of thetreatment chamber by a plurality of rigid radial members.

41-. In a vibrating device according to claim 3, wherein the edges ofthe tubular member are contoured to receive edges of the adjacentjackets of the insulative sleeve.

5. In a vibrating device according to claim 1, which further includes atleast two flexible bands surrounding opposite sides of the wall of thetreatment chamber and affixed to the jacket of the insulative sleeve forrigidly connecting the sleeve to the chamber.

6. In a vibrating device according to claim 1, wherein the outer jacketof the sleeve is connected to the wall of the treatment chamber by anannular disc having a plurality of apertures therein.

7. In a vibrating device according to claim 6, wherein said aperturesare elongated slots disposed along circles of different radii in saiddisc with the slots of one circle overlapping the slots of adjacentcircles.

8. In a vibrating device according to claim 6, wherein the apertures arearranged in several rows with the apertures of one row being offset tothe apertures of the other rows.

9. In a vibrating device according to claim 8, wherein the apertures areelongated slots which overlap the slots of adjacent rows.

10. In a vibrating device according to claim 1, wherein the connectingelements consist at least partially of a material with a low heatconductivity.

1. In a vibrating device having a treatment chamber with the wallsurrounded by an insulator sleeve having an outer jacket, said chamberbeing supported in a frame which is provided with a vibration producingdevice, the improvements comprising a fixed clamping strap connected tothe frame, and connecting elements disposed between the wall of thetreatment chamber and the clamping strap to rigidly interconnect thechamber to the clamping strap, said connecting elements having across-sectional area which is small as possible to prevent transfer ofheat between the strap and the wall of the chamber.
 2. In a vibratingdevice according to claim 1, wherein the connecting elements areconstructed of a plurality of members disposed between the clampingstrap and the wall of the treatment chamber.
 3. In a vibrating deviceaccording to claim 2, wherein the member of the connecting elementsinclude a tubular member spaced from the wall of the treatment chamberby a plurality of rigid radial members.
 4. In a vibrating deviceaccording to claim 3, wherein the edges of the tubular member arecontoured to receive edges of the adjacent jackets of the insulativesleeve.
 5. In a vibrating device according to claim 1, which furtherincludes at least two flexible bands surrounding opposite sides of thewall of the treatment chamber and affixed to the jacket of theinsulative sleeve for rigidly connecting the sleeve to the chamber. 6.In a vibrating device according to claim 1, wherein the outer jacket ofthe sleeve is connected to the wall of the treatment chamber by anannular disc having a plurality of apertures therein.
 7. In a vibratingdevice according to claim 6, wherein said apertures are elongated slotsdisposed along circles of different radii in said disc with the slots ofone circle overlapping the slots of adjacent circles.
 8. In a vibratingdevice according to claim 6, wherein the apertures are arranged inseveral rows with the apertures of one row being offset to the aperturesof the other rows.
 9. In a vibrating device according to claim 8,wherein the apertures are elongated slots which overlap the slots ofadjacent rows.
 10. In a vibrating device according to claim 1, whereinthe connecting elements consist at least partially of a material with alow heat conductivity.